NEW YORK ( TheStreet) -- Facebook ( FB) hosted its big press event at the company's headquarters in Menlo Park, Calif., on Tuesday, unveiling what it calls Graph Search.

CEO Mark Zuckerberg said Graph Search is a new way to search the billion people and more than 240 billion photos on Facebook, as well as the social network's more than a trillion connections.

Clearly, though, it's early days for the technology, which is available only to a small number of people who use Facebook in U.S. English. Users can get Graph Search by signing up for a waitlist.

Zuckerberg was unable to say when Facebook might monetize the technology. Instead, the youthful Facebook supremo promised vaguely that "this could be a business over time."

Investors were underwhelmed by the news. Facebook's shares ended Tuesday's session down 2.7% at $30.10.

During his presentation, Zuckerberg emphasized that Graph Search is different from Web search, highlighting both the technology's scale and its constantly changing nature.

While Web search, say, takes a set of keywords and provides the best possible results that match them, Graph Search can combine phrases to search people, places, photos and other content that's been shared on the social network. Another difference is that every piece of content on Facebook has its own audience, and most content isn't public, according to Facebook.

"We've built Graph Search from the start with privacy in mind, and it respects the privacy and audience of each piece of content on Facebook," wrote Tom Stocky, Facebook's director of product management, in a blog post on Tuesday. "It makes finding new things much easier, but you can only see what you could already view elsewhere on Facebook."

The invitation sent out by Facebook last week summoned journalists to "come and see what we're building," prompting intense speculation. Rumors swirled about possible search engine news, a streaming video deal with Netflix ( NFLX), or a phone announcement. Neither the Netflix deal nor a smartphone, however, materialized on Tuesday.

-- Written by Chris Ciaccia in Menlo Park and James Rogers in New York.